The present invention relates to an apparatus for sensing a characteristic of a segment of traveling yarn as the yarn travels through a slot of a sensing apparatus.
It is known to measure a yarn by sensing the shadow cast on a light sensitive element by the yarn or a reflection of the yarn. It is also known to measure a yarn by sensing changes in the electrical capacity of a condenser due to the presence of the yarn in an electrical field generated by the condenser. Such apparatuses are used, for example, on textile machines to monitor the production of yarn. In this respect, the accuracy of the yarn measurements can be impaired due to the presence of dust, yarn byproduct and other interfering matter.